**1. What are the 6 types of ASTM?**
ASTM International categorizes its standards into six primary types:
- **Standard Specification**: Defines requirements for materials, products, or services.
- **Standard Test Method**: Describes procedures to assess properties or performance.
- **Standard Practice**: Outlines recommended procedures or operations.
- **Standard Guide**: Provides information or options without strict requirements.
- **Standard Classification**: Systematically groups materials, products, or systems.
- **Terminology Standard**: Defines terms, symbols, or abbreviations used across standards.
**2. What do ASTM levels mean?**
ASTM "levels" typically refer to performance tiers within specific standards, such as medical face masks (ASTM F2100). For example:
- **Level 1**: Low barrier protection (e.g., for general use with minimal fluid exposure).
- **Level 2**: Moderate barrier protection (e.g., for procedures with light/moderate fluid exposure).
- **Level 3**: High barrier protection (e.g., for surgical settings with heavy fluid exposure).
**3. What do ASTM numbers mean?**
ASTM standards are labeled with alphanumeric codes (e.g., **ASTM A36** or **ASTM F2100**). The letter denotes the general category:
- **A**: Ferrous metals (e.g., steel).
- **B**: Nonferrous metals (e.g., copper).
- **C**: Ceramics, concrete, masonry.
- **D**: Plastics, textiles, petroleum.
- **E**: Miscellaneous topics (e.g., fire safety, testing).
- **F**: Materials for specific applications (e.g., medical devices).
The number is unique to the standard (e.g., **F2100** covers medical face masks).
**4. What is the difference between ASTM Level 3 and Level 1?**
In the context of medical face masks (ASTM F2100):
- **Level 1**: Lower fluid resistance (80 mmHg pressure), suitable for low-risk settings.
- **Level 3**: Highest fluid resistance (160 mmHg pressure), designed for high-risk surgical environments.
Level 3 masks also have stricter requirements for filtration efficiency (≥98% bacterial filtration) compared to Level 1 (≥95%).
**5. Where can I read ASTM standards?**
Access ASTM standards via:
- **ASTM Compass Platform**: Official repository (https://www.astm.org), requires a subscription.
- **University/Library Access**: Many institutions provide free access through their libraries.
- **Purchase Individual Standards**: Buy PDFs or hard copies directly from ASTM.
- **Third-Party Platforms**: Some standards may be available on platforms like Techstreet or ANSI Webstore.
